Oil, conventional or synthetic

[Tev62]

What the Honda people, who made the motor, put in the user manual.

[michael1954]

Use Motul Full Synthetic, 10W-40. Motul 7100 in the Hondas, and Motul 300AV in the Kawasaki. I put semi-synthetic in the 82' GS1100E, but not really riding it much yet, just turning it over weekly while it waits its turn in line after the DLX. May switch to better oil when it gets on the road.

[peterbaron]

Use Motul Full Synthetic, 10W-40. Motul 7100 in the Hondas, and Motul 300AV in the Kawasaki. I put semi-synthetic in the 82' GS1100E, but not really riding it much yet, just turning it over weekly while it waits its turn in line after the DLX. May switch to better oil when it gets on the road.

^^ +1 ^^ ....and OEM oil filter, to make my CB1100 happy

[rboe]

When I had my KZ550 Ltd I changed the oil every 2000 miles with Golden Spectro syn-blend oil. At 20K miles the shop did a compression test and I had a minimum of 190psi in each cylinder. Typical was 150psi (even in review in a bike magazine that only changed the oil at 10K after the initial break in oil change - what they deemed a typical owner would do.

For years I swore on syn-blended oil but looking back I suspect frequent oil changes had more to do with it so I stand behind Frulk on this one.

So I use syn-blend on the XR650L, the CB's (and other bikes) get full syn. From what I've seen in tests, these choices give me better protection in the Phoenix heat and gives higher mileage. So that drives my choice. When I lived in Duluth, MN full syn oil made starting an engine in the cold easier.

Now a fellow I met on Facebook that is nationally known for his builds of Vincent V twins (and others I don't recall) had had engine failures going from full synthetic back to dino oil. I don't understand it, don't have any experience with it but raise it in case others have seen it - and as a cautionary tale for folks considering switch back.

[tod.branko_imp]

Interesting, you all use synthetic. I just looked in the owners manual and it recommends Pro Honda GN4, SAE 10W-30 or equivalent motor cycle oil. Being air cooled vs water cooled do you think it matters? Just curious if synthetic is better for an air cooled engine but not necessary? Is there some real or psychological benefit to synthetic instead of using conventional oil?

I don't know about REAL benefit tbh, but I'll try to explain my decision.

From what I understand, synthetic oil has carefully engineered uniform sized molecules that are more resilient to temperature differences. Synthetic oils are usually recommended for performance engines, and motorcycles have high revving engines I consider them performance engines by definition. As I live in extreme heat (for reference today is probably going to be around 120°F out on the road) I use 10w60 oil, and to find a mineral oil with similar qualities I would be looking at a very thick mineral oil, and in my head I can't justify stressing the engine with thickness when I can just put in something with optimal thickness buy better quality.

'14 CB1100 STD 5 speed

[rboe]

This is the first time I've seen an oil thread devolve this way.

And we wonder why more women don't ride (or join forums )

[Cormanus]

Thank you Rboe. That’s the end of that discussion. Back to oil, please.

[Cormanus]

If anyone wonders, I edited the offending post and deleted the encouragement. This forum doesn’t Ed those sorts of conversations.

[tod.branko_imp]

If anyone wonders, I edited the offending post and deleted the encouragement. This forum doesn’t Ed those sorts of conversations.

Acknowledged. I apologize for steering in that direction, won't happen again

'14 CB1100 STD 5 speed

[Cormanus]

No apology necessary, tod, but thank you.

PS: I don’t know what word my autocorrect turned into ‘Ed’.